nhuwar said:
Building such an amp *IS* a box of cans of worms, and if one does not go and open most of them...they'll get opened at some inconvenient time and will likely bite one's backside in a most painful fashion.
In any case, I've seen no reason to doubt the ~70W limit on output power for excellent sonics. Make it bigger and the small power suffers. That is about all that keeps me from building a truly nutsy amp...that and I don't own any Maggies...
cheers,
Douglas
Packaging idea!
OK Jeff, you can take this or leave it ;-) but
Since you're going to need Mr Fusion Home Energy Reactor to power these amps and you need good robust packaging;
How about an industrial control box with a window in the front and Dymo labels? (see attachment for a "concept")
You might consider adding a third MV rectifier...
Wear your goggles when you fire it up; one.. point.. eight... kilovolts!
Mount it between the seats of your Mustang. Surely it will do 88 MPH.
OK enough
OK Jeff, you can take this or leave it ;-) but
Since you're going to need Mr Fusion Home Energy Reactor to power these amps and you need good robust packaging;
How about an industrial control box with a window in the front and Dymo labels? (see attachment for a "concept")
You might consider adding a third MV rectifier...
Wear your goggles when you fire it up; one.. point.. eight... kilovolts!
Mount it between the seats of your Mustang. Surely it will do 88 MPH.
OK enough
Attachments
I have two separate PSUs and they are stacked to avoid the large biasing resistor for the 304TL (just think to the Loftin White and variants). The EXO99 choke and that Rx are fixing the bias for the 304TL, to make it more clear
801A grid:-9V
801A cathode: 0V
801A anode=304TL grid: +280V
304TL cathode: +330V
304TL anode: +1200V
The OPT is returned to the 304TL cathode.
I loved that amp but I am not using any more 304TL as they were way too hot
In the same amp I used GM70, 813, 304TL and 75TL. Going to give 845 a try soon.
Disclaimer: the high voltages can kill! Beware!
Gianluca
Gianluca
How about posting your schematic.
grazie e buonna pasqua!
Gianluca
How about posting your schematic.
grazie e buonna pasqua!
Sure. 801A was running at 20mA.
buona pasqua.
gianluca
Gianluca,
So how did you like the sound of the different tubes that you tried? I have made a 211 and 845 amp, but am interested in the 304tl and gm70 also.
Hello Gianluca...your original post goes back to 2009 on your 304TL amplifier. Is yours still in use? The primary of my Power Transformer failed and I was wondering how you might be able to help me with your design?Me! Me! Mine.
this is my 304TL amp
Rx sets the bias for the 304TL. You need two separate PSUs and, what else?, yes heating the tube is not an easy task.
Good luck with the OPT, not easy to find a good one.
Gianluca
Many thanks from Canada,
Bill Slaunwhite
hey. no, I dismantled it years ago as it was way too hot; actually it morfed into other amps including a 801A-75TL directly coupled ... i loved it madly. ask a question, I might be able to answer
Hi Gianluca...I am loving my 304TL as well but not so much now as it's not working The Croatian gentleman who built this amp said that this is a technicians' amp and I understand why. Getting someone to service this is very difficult and getting a custom replacement power transformer is almost impossible...I am still researching this. The designer (Kruno) was likely nearing his 70's, if not already in his 70's when he built it and he owned it for 4 years with no issues. When he placed it up for sale, I happened to see it and had to have it!!! It looked so sexy and beautiful...I fell in love...LOL LOL! He seems like a very practical hands-on kind of designer and we are still in communication. He redesigned the power transformer and that is what I am trying to have manufactured now. I live in Canada and no one here can help me...I am now searching within the United States.
I've attached some files for you to look at but only really to satisfy your curiosity perhaps? The second attachment is what I send to a transformer manufacturer to get a quote.
All the best to you Gianluca! Happy Easter!
The Croatian gentleman who built this amp said that this is a technicians' amp and I understand why. Getting someone to service this is very difficult and getting a custom replacement power transformer is almost impossible...I am still researching this. The designer (Kruno) was likely nearing his 70's, if not already in his 70's when he built it and he owned it for 4 years with no issues. When he placed it up for sale, I happened to see it and had to have it!!! It looked so sexy and beautiful...I fell in love...LOL LOL! He seems like a very practical hands-on kind of designer and we are still in communication. He redesigned the power transformer and that is what I am trying to have manufactured now. I live in Canada and no one here can help me...I am now searching within the United States. I've attached some files for you to look at but only really to satisfy your curiosity perhaps? The second attachment is what I send to a transformer manufacturer to get a quote.
All the best to you Gianluca! Happy Easter!
just one chassis! so comfortable
mine was 4 chassis and 100kg or so.
you might try to call electraprint, maybe J Elliano can wind one for you
https://www.electra-print.com/index.php
mine was 4 chassis and 100kg or so.
you might try to call electraprint, maybe J Elliano can wind one for you
https://www.electra-print.com/index.php
Hi Gianluca, you are funny saying the chassis is so comfortablejust one chassis! so comfortable
mine was 4 chassis and 100kg or so.
you might try to call electraprint, maybe J Elliano can wind one for you
https://www.electra-print.com/index.php
you have a great sense of humour. I will reach out to Electra-Print if I don't make any headway with the others I have calls in with. My feelings now feel like I will have to get a PT with a higher wire gauge for the primary. It will make the transfomer bigger (taller) but as long as it still fits in the space then I am okay with that. Still trying to figure it out but I need to speak to transformer winder specialists to hear if that will work. Thanks for your thoughts! Hi petertub, thanks for your input. I talked to my technician about a switching power supply but we decided we may go down that road if I can't get an updated power transformer. I think old-school may be the way to go as I don't want to modify the chassis. I am not a technician so I am only guessing that reply.
hello - I am interested in building 304TL SE amp and found your schematics with 6J5 driving 304TL... How is this combo been working for you? Have you changed output transformer? It looks like your new xformer has 1.5kV winding I assume to power 304? Is 6j5 going to be able to provide enough drive for this?Hi Gianluca...I am loving my 304TL as well but not so much now as it's not working
I've attached some files for you to look at but only really to satisfy your curiosity perhaps? The second attachment is what I send to a transformer manufacturer to get a quote.
All the best to you Gianluca! Happy Easter!
Hello Superhik, my technical abilities are limited unfortunately but I can talk to you about this amp privately if you like and let you know my thoughts? My personal email is wgs"at"outlook.com. Perhaps we can talk if you would like to leave me with your phone number...provided you are in Canada or the US?